1. Field of the Invention
The present application relates to devices for the vitrification of biological samples, including embryos, oocytes and biological tissues. Suitably, the devices are automated devices which require little if any operator intervention or sample handling, thereby reducing contamination, improving success rates and increasing efficiency. Also provided are methods of vitrifying a biological sample, suitably using the disclosed devices.
2. Background of the Invention
Freezing and preservation of biological samples had traditionally been carried out using a slow-freezing process. Those methods were accomplished by tabletop machines that slowly cooled a sample over the period of several hours to cryogenic temperatures. These “slow freezing methods” have recently being supplanted by sample “vitrification,” which allows for rapid freezing and storing of specimens in a matter of minutes instead of hours.
However, current vitrification devices require significant operation by a skilled lab technician. Success rates of vitrification and warming viable samples vary widely depending on the method used and the skill of the lab technician performing the procedure. Such methods traditionally require a lab technician to prepare individual samples for freezing, handle each separately and carry out specified methods. These methods, however, are not only time-consuming and inefficient, but can result in variations in sample vitrification due to differences in technician training and technique. This makes it extremely difficult to evaluate and compare various protocols. In addition, many manual vitrification methods expose the specimen directly to liquid nitrogen (i.e., open system), which provides rapid cooling (vitrification), but can lead to introduction of contaminants (fungi, pathogens etc.) to the specimen, as well as sample loss and damage.
The inventors have identified a need for protocols and devices that can be used to repeatedly and efficiently vitrify biological samples, including for use in fertility preservation and tissue banking.